utils-std

commit: 8ee8d7b92bfdda109c83d24151c468a487ab0a8d
parent f5476d2af4cdd3e3a7973e9028b59178bb48b63d
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Fri, 27 Sep 2024 10:17:59 +0200

cmd/cat: use auto_fd_copy

Diffstat:
M
Makefile
6
++++--
M
cmd/cat.c
87
++++++++++++++-----------------------------------------------------------------
M
test-cmd/cat.sh
2
+-

3 files changed, 20 insertions(+), 75 deletions(-)
diff --git a/Makefile b/Makefile
@@ -78,8 +78,6 @@ format: $(C_SOURCES)
 lib/sys_signame.c: lib/sys_signame.sh
 	lib/sys_signame.sh >|lib/sys_signame.c
 
-cmd/cat: cmd/cat.c config.mk Makefile
-
 cmd/date: cmd/date.c lib/iso_parse.c Makefile
 	$(RM) -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
 	$(CC) -std=c99 $(CFLAGS) -o $@ cmd/date.c lib/iso_parse.c $(LDFLAGS) $(LDSTATIC)
@@ -183,6 +181,10 @@ cmd/expr: cmd/expr.tab.c Makefile
 	$(RM) -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
 	$(CC) -std=c99 $(CFLAGS) -D_POSIX_C_SOURCE=200809L -o $@ cmd/expr.tab.c $(LDFLAGS) $(LDSTATIC)
 
+cmd/cat: cmd/cat.c lib/fs.c lib/fs.h Makefile config.mk
+	$(RM) -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
+	$(CC) -std=c99 $(CFLAGS) -o $@ cmd/cat.c lib/fs.c $(LDFLAGS) $(LDSTATIC)
+
 cmd/install: cmd/install.c lib/mode.c lib/user_group_parse.c lib/user_group_parse.h lib/fs.c lib/fs.h lib/lib_mkdir.c lib/lib_mkdir.h Makefile config.mk
 	$(RM) -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
 	$(CC) -std=c99 $(CFLAGS) -o $@ cmd/install.c lib/mode.c lib/user_group_parse.c lib/fs.c lib/lib_mkdir.c $(LDFLAGS) $(LDSTATIC)
diff --git a/cmd/cat.c b/cmd/cat.c
@@ -3,11 +3,12 @@
 // SPDX-License-Identifier: MPL-2.0
 
 #define _POSIX_C_SOURCE 200809L
-#define _GNU_SOURCE // splice
+#include "../lib/fs.h"
+
 #include <assert.h>
 #include <errno.h>
-#include <fcntl.h>  // open, O_RDONLY, splice
-#include <stdint.h> // SIZE_MAX
+#include <fcntl.h>  // open, O_RDONLY
+#include <limits.h> // SSIZE_MAX
 #include <stdio.h>  // fprintf, BUFSIZ
 #include <stdlib.h> // abort
 #include <string.h> // strerror, strncmp
@@ -15,72 +16,6 @@
 
 const char *argv0 = "cat";
 
-static int
-concat(int fd, const char *fdname)
-{
-	ssize_t c;
-	char buf[BUFSIZ];
-
-	assert(errno == 0);
-	while((c = read(fd, buf, sizeof(buf))) > 0)
-	{
-		assert(errno == 0);
-		if(write(STDOUT_FILENO, buf, (size_t)c) < 0)
-		{
-			fprintf(stderr, "%s: error: Failed writing: %s\n", argv0, strerror(errno));
-			errno = 0;
-			return 1;
-		}
-	}
-
-	if(c < 0)
-	{
-		fprintf(
-		    stderr, "%s: error: Failed reading from file '%s': %s\n", argv0, fdname, strerror(errno));
-		errno = 0;
-		return 1;
-	}
-
-	return 0;
-}
-
-#ifdef HAS_SPLICE
-#define FD_COPY_SPLICE_FLAGS SPLICE_F_MOVE | SPLICE_F_NONBLOCK | SPLICE_F_MORE
-static int
-fd_copy(int fd, const char *fdname)
-{
-	while(1)
-	{
-		assert(errno == 0);
-		ssize_t ret = splice(fd, NULL, STDOUT_FILENO, NULL, SIZE_MAX, FD_COPY_SPLICE_FLAGS);
-
-		if(ret == 0) break;
-
-		if(ret < 0)
-		{
-			switch(errno)
-			{
-			case EINVAL:
-				errno = 0;
-				return concat(fd, fdname);
-			case EAGAIN:
-				errno = 0;
-				continue;
-			default:
-				fprintf(
-				    stderr, "%s: error: Failed copying file '%s': %s\n", argv0, fdname, strerror(errno));
-				errno = 0;
-				return 1;
-			}
-		}
-	}
-
-	return 0;
-}
-#else // HAS_SPLICE
-#define fd_copy concat
-#endif // HAS_SPLICE
-
 static void
 usage(void)
 {
@@ -116,8 +51,9 @@ main(int argc, char *argv[])
 
 	if(argc < 1)
 	{
-		if(fd_copy(STDIN_FILENO, "<stdin>") != 0)
+		if(auto_fd_copy(STDIN_FILENO, STDOUT_FILENO, SSIZE_MAX) < 0)
 		{
+			fprintf(stderr, "%s: error: Failed copying data from <stdin>: %s\n", argv0, strerror(errno));
 			return 1;
 		}
 	}
@@ -127,8 +63,10 @@ main(int argc, char *argv[])
 		{
 			if(strncmp(argv[argi], "-", 2) == 0)
 			{
-				if(fd_copy(STDIN_FILENO, "<stdin>") != 0)
+				if(auto_fd_copy(STDIN_FILENO, STDOUT_FILENO, SSIZE_MAX) < 0)
 				{
+					fprintf(
+					    stderr, "%s: error: Failed copying data from <stdin>: %s\n", argv0, strerror(errno));
 					return 1;
 				}
 			}
@@ -147,8 +85,13 @@ main(int argc, char *argv[])
 					return 1;
 				}
 
-				if(fd_copy(fd, argv[argi]) != 0)
+				if(auto_fd_copy(fd, STDOUT_FILENO, SSIZE_MAX) < 0)
 				{
+					fprintf(stderr,
+					        "%s: error: Failed copying data from file '%s': %s\n",
+					        argv0,
+					        argv[argi],
+					        strerror(errno));
 					return 1;
 				}
 
diff --git a/test-cmd/cat.sh b/test-cmd/cat.sh
@@ -38,7 +38,7 @@ fi
 if [ "$(uname -s)" = "NetBSD" ]; then
 	skip readslash "NetBSD allows to read directories"
 else
-	t --exit=1 readslash / "cat: error: Failed reading from file '/': Is a directory
+	t --exit=1 readslash / "cat: error: Failed copying data from file '/': Is a directory
 "
 fi